During the Protestant Reformation depicting the image of saints in churches and on headstones was forbidden as it was seen as idolatry and as they were perfect beings, could not be created by imperfect men. As Christianity became more tolerant saints started to reappear.
Apostles on Headstones
The main 4 saints from the Bible are the apostles Matthew, Mark, Luke and John. They are often found at the four corners of monuments in their form as animal kings mentioned in both Ezekiel 1:10 and Revelation 4:7.
St. Matthew is shown as a winged man. Man is king of creation, as he is in Gods image.
St. Mark is depicted as a winged lion as it is king of the beasts.
St. Luke is a winged bull or ox. This is because they are the kings of domesticated animals.
St. John is an eagle, king of the birds.
Saints on Headstones
Other saints on headstones are also identified via objects concerning their role or previous employment.
St. Peter is usually pictured holding the keys to heaven or the book of life. The key has a trefoil design.
St. Matthew as a tax collector holding a purse .
St. Mark is depicted holding a book and palm frond
St. Luke was thought to be an artist so can hold brushes
St. John is represented by a young or femanine man. he may also hold a chalice with a snake in it
St. James is represented by the scallop shell
St. Bartholomew was de-fleshed so holds his own skin